May 7th, 2015
Advocates Say Precision Medicine Could Lead to Enormous Benefits
Personalized and precision medicine (PPM) could deliver hundreds of billions of dollars worth of improved health in the next 50 years in the United States, writes Victor Dzau, the new president of the Institute of Medicine, and coauthors in a Viewpoint published in the Lancet.
The authors used a health simulation model to estimate the effect of improved screening and risk prediction to treat people at high risk for six conditions: cancer, diabetes, heart disease, high blood pressure, lung disease, and stroke. They then calculated the resulting gains in life expectancy and quality-adjusted life expectancy.
They calculated that reducing heart disease by 50% “would generate a staggering $607 billion in improved health over 50 years.” More modest reductions of less prevalent diseases would produce smaller but still quite impressive benefits: even a 10% reduction in diabetes and cancer would generate $96 billion and $70 billion, respectively, they write.
The authors express concern that because the “real benefits of PPM innovations accrue over” a long time “as individuals live longer, healthier lives,” private payers in the U.S. may not be inclined to cover the PPM interventions. Single-payer systems in Europe and elsewhere may be more far-sighted, they speculate.
Sanjay Kaul provided the following response to the paper:
The projections from the modeling exercise are predicated on two key assumptions for which there is little or no evidentiary support. First, the claim that genetic testing can lead to identification of individuals at extraordinary risk of developing CV disease in whom ‘aggressive preventive and interventional strategies have a much greater likelihood of success’ rests on a shaky foundation. Take the example of 9p21, the best studied genetic variant for CHD. It is associated with approximately 40% increased risk, a relatively small effect size which is clearly not commensurate with ‘an extraordinary risk of developing CV disease’. Given the feeble prognostic utility, it should not come as a surprise that there is precious little evidence to show that genetic variants, either singly or in combination, offer incremental improvement in risk discrimination or net reclassification compared to conventional risk models. Second, empirical support for the notion that genetic knowledge of increased susceptibility to CV disease will motivate individuals to modify their lifestyle and improve health is currently lacking. Thus, the predictive utility of genetic tests in therapeutically modifying CV risk remains an unanswered question. The recent announcement of the Precision Medicine Initiative by President Obama has created quite a buzz within the medical and research community. However, the transition of Precision Medicine from a buzzword to clinical reality should be driven by tangible evidence of benefit, rather than some rosy predictions of value derived from a modeling exercise.”